So I lost my Windows 10 product key, is there any way to view it on Windows 10 alone? I've tried finding it through CMD but I could only find the Product ID which is something different. I'm having W10 issues and want to do a fresh reinstall but, obviously I don't have the product key. Any help?

While playing on my PC, my young brother threw some toy on my screen :/, and now I see like 30-50 stuck pixels (it is like a circle of red/green/red pixels) so, is there any way to fix it home? or should I take it to some expert ?